Raising Compresion

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Garnet
Posts: 3108
Joined: Tue Aug 03, 2010 6:24 pm
Location: Victoria BC Canada

Raising Compresion

Post by Garnet »

I want to bump the CR on one of my R75/5 engines. It has a freash top end 10,000 miles ago with new 1st over 9:1 KS pistons.

I plan on removing the stock .5mm cylinder base gasket which should put me up in the 9.5:1 range. Aside from measuring the squish band and valve clearance is there anything else I should be aware of?

Any other comments welcome.
Garnet

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mattcfish
Posts: 754
Joined: Mon Aug 02, 2010 11:18 pm

Re: Raising Compresion

Post by mattcfish »

Garnet wrote:I want to bump the CR on one of my R75/5 engines. It has a freash top end 10,000 miles ago with new 1st over 9:1 KS pistons.

I plan on removing the stock .5mm cylinder base gasket which should put me up in the 9.5:1 range. Aside from measuring the squish band and valve clearance is there anything else I should be aware of?

Any other comments welcome.
I've seen this done on /5's and early /6's. Squish band and minimum valve clearance check, check and check again.
That's a 308 cam on your R75/5 right?
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Garnet
Posts: 3108
Joined: Tue Aug 03, 2010 6:24 pm
Location: Victoria BC Canada

Re: Raising Compresion

Post by Garnet »

mattcfish wrote: That's a 308 cam on your R75/5 right?
Yes, at original 0 timing.
Garnet

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